Supply Of Fuels Research Articles

Modeling and optimization of an ocean thermal energy conversion system for remote islands electrification

Electrification of remote zones is often characterized by high energy costs as a result of the fossil fuels supply and cost associated to its logistic. This study performs a theoretical model and optimization of an ocean thermal energy conversion (OTEC) system coupled to an organic Rankine cycle (ORC) generator for small scale applications in the San Blas archipelago (Panama). The gross electric power has been previously set at 125 kW for the eleven working fluids selected: ammonia, R152a, R1234yf, R1234ze, R125, R134a, R161, propane, isobutene, RE143a and decafluorobutane. Results show R1234yf gets the maximum thermodynamic and net electric efficiency (3.60% and 2.57%, respectively). Ammonia reaches the maximum net electric power (99.3 kW) and, thus, the lowest pumping losses (20.59% of the gross). Besides, despite decafluorobutane shows slightly lower electric power (98 kW) and efficiencies, this fluid does not present environmental hazardous features. Sensitivity analyses show that all performance parameters of the plant are strongly affected by deep and surface seawater temperature variation. Finally, for a surface seawater temperature of 30 °C and deep 5 °C, the net electric power reached is 94.6 kW for R1234yf, 99.3 kW for ammonia and 98.0 kW for decafluorobutane. The net electric efficiency is 2.57%, 2.53% and 2.42%, and the total area required by the heat exchangers is 890 m2, 940 m2 and 986 m2, respectively.

A trilevel model against false gas-supply information attacks in electricity systems

The interdependence between natural gas and electricity systems is increasing rapidly due to the growing reliance on natural gas-fired generating units. Availability of natural gas for gas-fired generating units can impact the secure operation of electricity systems. Fuel supply shortage for gas-fired units can be caused by uncertain interruptible supply contracts and incorrect supply information. This article proposes a trilevel min-max-min defender-attacker-operator optimization problem to provide the power system operator a screening methodology that allocates a limited budget for best protecting critical fuel supply information, and also the strategies to sign firm supply contract to reduce natural gas supply uncertainties. We employ a column and constraint generation (C&CG) algorithm to solve the proposed problem. We illustrate the effectiveness of this trilevel formulation using a case study based on IEEE 24-node test system.

Combustion monitoring in an industrial cracking furnace based on combined CFD and optical techniques

Ethylene is one of the most important building blocks of current chemical industry with a global production of 150 million tons in 2016. Most ethylene nowadays is produced via thermal cracking with steam of fossil feedstocks in cracking furnaces. This process accounts for approximately 8% of the petrochemical sector primary energy consumption making it the single most energy-consuming process in the chemical industry. Combustion of hydrocarbon fuels supplies the required energy to cracking units resulting in substantial CO2 emissions. Also, new emission regulations have a strong influence on older units with partially premixed burners, which produce larger amounts of NOx than modern designs. Therefore, an improvement of energy efficiency and a reduction of pollutants in cracking furnaces are environmentally and economically driven. In this work, both issues have been addressed based on numerical (CFD) techniques and experimental measurements at the plant. Firstly, to monitor burner efficiency a new methodology based on CFD calculation of OH- and CH- radicals via reduced chemical kinetics, combined with industrial-scale experimental validation through flame spectroscopic measurements and UV CCD cameras, has been carried out. Based on these measurements, a quick diagnosis of combustion performance by flame emission chemiluminescence can be made, which has successfully tested for the first time at full-scale industrial cracking furnaces. Secondly NOx emissions have been simulated by the usual approach of reduced chemistry and post-processing over the CFD fields, demonstrating with plant data at the stack that reasonable predictions can be achieved in this context. The method has been used to study modifications of burner geometry to abate NOx formation.

Risk Assessment of Fuel Supply Pipelines: Kalecik Power Plant Case Study

AbstractMany power plants use fossil fuels to produce electrical energy. A safe fuel supply is an important issue in power plant operation. Although traditional use of pipeline systems is a common ...

Recent Advances in Noble Metal Catalysts for Hydrogen Production from Ammonia Borane

Interest in chemical hydrogen storage has increased, because the supply of fossil fuels are limited and the harmful effects of burning fossil fuels on the environment have become a focus of public concern. Hydrogen, as one of the energy carriers, is useful for the sustainable development. However, it is widely known that controlled storage and release of hydrogen are the biggest barriers in large-scale application of hydrogen energy. Ammonia borane (NH3BH3, AB) is deemed as one of the most promising hydrogen storage candidates on account of its high hydrogen to mass ratio and environmental benignity. Development of efficient catalysts to further improve the properties of chemical kinetics in the dehydrogenation of AB under appropriate conditions is of importance for the practical application of this system. In previous studies, a variety of noble metal catalysts and their supported metal catalysts (Pt, Pd, Au, Rh, etc.) have presented great properties in decomposing the chemical hydride to generate hydrogen, thus, promoting their application in dehydrogenation of AB is urgent. We analyzed the hydrolysis of AB from the mechanism of hydrogen release reaction to understand more deeply. Based on these characteristics, we aimed to summarize recent advances in the development of noble metal catalysts, which had excellent activity and stability for AB dehydrogenation, with prospect towards realization of efficient noble metal catalysts.

Production of a cyanobacterium-based biodiesel by the heterogeneous biocatalyst of SBA-15@oleate@lipase

Rising world demand coupled with diminishing supply of fossil fuels and petroleum products have led to look for alternative renewable and clean fuels such as biodiesel. The production of biodiesel can be facilitated with suitable biocatalysts. In the present study, a mesoporous silica of SBA-15 modified with oleic acid and a solvent tolerant lipase from Actinomadura sediminis (SBA-15@oleate@lipase) was designed as the heterogeneous biocatalyst with maximum activity by a protein loading of 32.0 mg per gram of the support. The maximum immobilization efficiency (68%) and yield (80%) were also obtained at 200 µg ml−1 of the protein with reaction time of 60 min. The enzymatic trans-esterification reaction was catalyzed for converting oil of the cyanobacterium Synechococcus elongatus into biodiesel with an 85% ± 3.2 yield under optimized conditions. The designed heterogeneous biocatalyst revealed a high efficiency towards palmitoleic acid (C16:1) in the microalgal oil that is one of the best fatty acids to produce a high-quality biodiesel. This work also highlights the simultaneous combination of purification and immobilization of the bacterial lipase by interfacial activation mechanism, to the synthesis of a solid biocatalyst for production of a cyanobacterium-based biodiesel.

Cell-free styrene biosynthesis at high titers

Styrene is an important petroleum-derived molecule that is polymerized to make versatile plastics, including disposable silverware and foamed packaging materials. Finding more sustainable methods, such as biosynthesis, for producing styrene is essential due to the increasing severity of climate change as well as the limited supply of fossil fuels. Recent metabolic engineering efforts have enabled the biological production of styrene in Escherichia coli, but styrene toxicity and volatility limit biosynthesis in cells. To address these limitations, we have developed a cell-free styrene biosynthesis platform. The cell-free system provides an open reaction environment without cell viability constraints, which allows exquisite control over reaction conditions and greater carbon flux toward product formation rather than cell growth. The two biosynthetic enzymes required for styrene production were generated via cell-free protein synthesis and mixed in defined ratios with supplemented L-phenylalanine and buffer. By altering the time, temperature, pH, and enzyme concentrations in the reaction, this approach increased the cell-free titer of styrene from 5.36 ± 0.63 mM to 40.33 ± 1.03 mM, the highest amount achieved using biosynthesis without process modifications and product removal strategies. Cell-free systems offer a complimentary approach to cellular synthesis of small molecules, which can provide particular benefits for producing toxic molecules.

Carbon Leakage Along with the Green Paradox Against Carbon Abatement? A Review Based on Carbon Tax

Abstract Research background: Insufficient global cooperation in carbon pricing against global warming has the risk of global carbon emissions rise because of carbon leakage. The effect of a carbon tax on the present supply of fossil fuels is also valuable in regard to global carbon emissions. Purpose: The purpose of this study is to gain more insights into the effects of carbon leakage along with the green paradox on global carbon emissions by reviewing the relevant literature. Research methodology: We provide the problem linked to carbon leakage and the green paradox in the introduction. Then, the effects of carbon leakage and the green paradox on global carbon emissions are elaborated separately. Finally the mutual effects of carbon leakage and the green paradox are reviewed comprehensively. Results: It is seen that various factors like interest rates, fossil fuel extraction costs, the fossil fuel reserves to be discovered in the future and carbon tax incidence are equally important determinants in regard to global carbon emissions. Novelty: This study provides an insight into the mutual effects of carbon leakage and the green paradox on global carbon emissions by reviewing the primary literature in the field.

Strategic Planning of Integrated Biofuel and Petroleum Fuel Supply Chains

Strategic Planning of Integrated Biofuel and Petroleum Fuel Supply Chains

Sedekah Jelantah: Sebuah Inisiatif untuk Mempromosikan Sistem “Waste Management” dan untuk Menciptakan Komunitas Mandiri melalui Biofuel

WASTE COOKING OIL DONATION: AN INITIATIVE TO PROMOTE “WASTE MANAGEMENT” SYSTEMS AND TO CREATE AN INDEPENDENT COMMUNITY THROUGH BIOFUELS. The supply of fossil fuels has been running low, and fossil fuel needs cannot be met by fossil fuels. Indonesia is in dire need of a substitute energy source that is not only available sustainably but also to produce renewable energy. One alternative is energy based on used cooking oil. This idea is a very interesting idea because used cooking oil can be a very promising source of fuel. Unfortunately all this used cooking oil has not been utilized properly, even polluting the soil and water. The purpose of this community program is to communicate and socialize the importance of distributing used cooking oil to become a renewable energy source, thus preventing pollution problems due to waste cooking oil disposal. This community development is carried out by developing a system within the community to ensure the collection of used cooking oil for the sustainability of the renewable energy program as an alternative resource for energy that is environmentally friendly. This initiative was given the name Sedekah Jelantah program.

Measuring the Importance of Decision-Making Criteria in Biofuel Production Technology Selection

Environmental problems, combined with a finite supply of fossil fuels, have made the use of renewable energy sources necessary. Biomass is a renewable source of energy that has played a very important role in energy production in recent years. Because there are a number of technologies that can be used to convert biomass into energy, it is important to select the best option. The fact that multiple options are available that need to be evaluated based on a set of decision-making criteria makes this a multicriteria decision-making problem. This paper takes the first step in proposing an evaluation framework and identifying the importance of the relevant decision-making criteria in biofuel production technology selection. To determine the importance of the selection criteria, experts were asked to respond to an online questionnaire based on the best–worst method. The results indicate that air pollution, land use change, and human expertise are the three most important criteria for selecting the best biofuel production technology in our case country, Iran.

Development of Linear Vernier Hybrid Permanent Magnet Machine for Wave Energy Converter

Today, due to the limited supply and rapid consumption of fossil fuels, transitioning towards renewable energy supplies has become more important than ever.. The purpose of this paper is to present a new linear permanent magnet vernier machine structure which is designed to capture wave energy and improve the performance of the prototype vernier machine. By halving the proposed vernier machine, amending gear ratio and changing the shape of permanent magnet (PM) and teeth, the performance of the proposed vernier machine increases compared to the prototype vernier machine. This novelty causes the proposed vernier machine to be lighter, more economical and more efficient than the prototype vernier machine. Moreover, the main parameters of the proposed vernier machine compared to the prototype vernier machine are improved, so that in the proposed vernier machine, induced voltage, PM flux and thrust force are increased by 30, 68 and 27% respectively. In addition, the ripple of thrust force is reduced by 5%, and the self-inductance is diminished by 55%. All analyses have been performed in the same conditions with the finite element method using Ansys Maxwell software.

Design of Hydrogen Fuel Supply Chain Distribution Network from The Potency of Fresh Fruit Empty Bunches

In Indonesia, the production of biomass is wasted because it is considered as “waste” that has no use anymore such as bagasse, rice grain skin, corn cob, and oil palm waste. Oil palm empty bunches have C and H chemical bonds, where most of the materials with chains C and H store heat energy so that hydrogen can be obtained as fuel. Process to convert a biomass into hydrogen is by gasification and pyrolysis. The purpose in this research is to design the distribution network from the potential fresh fruit empty bunches. The hydrogen produced is only 0.469% of the available potential and is similar to the existing of the used empty bunches potential. Selection of factory location is based on 4 criteria. From the criteria, obtained Labuhan Batu District as the best regencies in North Sumatra. Potential plantations can supply as much as 6,390,423,000 kgs with the ability of oil palm factory distribution of 1,469,797,290 kgs.

Production of Jatropha Methyl Ester

In a past span of years there is a huge development in the automobile field it creates a demand for petroleum products leads to insufficient supply of fuels and also it causes more pollution. Due to this all the developed and developing countries are focusing in producing biodegradable fuels to reduce the cost and demand of fossil fuels and mineral oils. Many researchers are identify that vegetable oils and biogas are the beat alternate to the mineral oils. Since the vegetable oils are eco-friendly and biodegradable so it plays the major role in production of alternate fuels. In this paper the production of jatropha ester and the tribological properties were studied. Transesterification process was carried out to produce the ester from jatropha curcas oil. Jatropha curcas oil is a non-edible oil, ester prepared from jatropha curcas oil was added with nano copper oxide particles to improve the wear resisting property and reduce the pollution.

The impact of unconditional cash transfer on fuel choices among ultra-poor in Pakistan: Quasi-experimental evidence from the Benazir Income Support Program

We analyze the impact of the unconditional cash transfer program, namely the Benazir Income Support Program (BISP) on fuel choices among ultra-poor in Pakistan using two rounds of household-level data collected in 2011 and 2016. The analysis based on regression discontinuity design shows that BISP cash transfer has a significant impact on interfuel substitution. Cash transfer increases the use of modern fuels among BISP beneficiaries. Besides, cash transfer also encourages the use of intermediate fuels, even in some cases traditional fuels. Cash transfer also increases the share of fuel expenses in total household expenses. Therefore, the fuel stacking theory provides a better explanation of interfuel substitution than the energy ladder theory of the cash transfer program. The provincial analysis shows that interfuel substitution exists due to cash transfer but varies from province to province, signifying the role of regional heterogeneities. The net impact on fuel choices may depend on the availability of different fuel components. From policy perspective, the expansion of the cash transfer program, as planned by the government, would require a reasonable investment in the energy sector to ensure an uninterrupted supply of modern fuels.

Emissions and performance analysis of diesel powered road vehicle equipped with real-time non-surfactant emulsion fuel supply system

Water-in-diesel (W/D) emulsion is one of the promising alternative fuel that improves the combustion efficiency of a diesel engine and simultaneously reduces harmful exhaust emissions. To ensure a stable emulsion, surfactant is used during the formation of W/D emulsion which causes additional costs for this alternative fuel. A device called as Real-Time Non-Surfactant Emulsion Fuel Supply System (RTES) was invented to eliminates the use of surfactant and rapidly supply the W/D emulsion to the engine. The efficiency of 1-ton light-duty diesel truck fueled with W/D emulsion fuel produced by RTES was tested. Two types of the experimental method were used which chassis dynamometer testing and on-road are testing. The optimum water percentage and vehicle speed were evaluated from the result of exhaust emissions and fuel consumption measurement. Chassis dynamometer testing showed that the optimum water percentage for DE2 were 6.5% and vehicle speed aimed at 52 km/h was selected as the optimum vehicle speed. In on-road testing, the urban route gave the deficient results for both exhaust emissions and fuel consumption which agree with chassis dynamometer testing result where emulsion fuel is not suitable to be used at low speed vehicle operation.

Different pretreatment technologies of lignocellulosic biomass for bioethanol production: An overview

Regarding the supply of fossil fuels, greenhouse gasses emission, global warming, and increasing fuel price; there is a need to find alternative energy resources, which are renewable, environmentally sustainable, and economically viable. Agro-industrial biomass such as sugarcane bagasse, rice and wheat straw, corn stover, and switchgrass, named as lignocellulosic biomass (LCB) which is inexpensive, abundant, renewable, and provides a unique natural resource for large-scale and cost-effective bio-energy production. During the production of biofuels, pretreatment is a necessary step due to the recalcitrant structure of LCB. Various pretreatment methods were employed with a different mechanism of action, feasibility, and practicability to produce high yield biofuels. Since many years ago, the development of an effective pretreatment method has been challenging due to the existence of barriers and obstacles. Besides, each pretreatment method has its advantage and disadvantage, which should be investigated to obtain a higher yield of bioethanol. In this paper, the recent findings regarding the application of various pretreatment techniques such as chemical, physical and biological methods for bioethanol production from LCBs have been reviewed. The limitations of the mentioned methods based on the existing barriers were explained, and the future recommendations were discussed.

Prospects of ocean-based renewable energy for West Africa’s sustainable energy future

PurposeThe limited supply of fossil fuels, constant rise in the demand of energy and the importance of reducing greenhouse emissions have brought the adoption of renewable energy sources for generation of electrical power. One of these sources that has the potential to supply the world’s energy needs is the ocean. Currently, ocean in West African region is mostly utilized for the extraction of oil and gas from the continental shelf. However, this resource is depleting, and the adaptation of ocean energy could be of major importance. The purpose of this paper is to discuss the possibilities of ocean-based renewable energy (OBRE) and analyze the economic impact of adapting an ocean energy using a thermal gradient (OTEC) approach for energy generation.Design/methodology/approachThe analysis is conducted from the perspective of cost, energy security and environmental protection.FindingsThis study shows that adapting ocean energy in the West Africa region can significantly produce the energy needed to match the rising energy demands for sustainable development of Nigeria. Although the transition toward using OBRE will incur high capital cost at the initial stage, eventually, it will lead to a cost-effective generation, transmission, environmental improvement and stable energy supply to match demand when compared with the conventional mode of generation in West Africa.Practical implicationsThis study will be helpful in determining the feasibility, performance, issues and environmental effects related to the generation and transmission of OBRE in the West Africa region.Originality/valueThe study will contribute toward analysis of the opportunities for adopting renewable energy sources and increasing energy sustainability for the West Africa coast regions.

Improving Fuel Economy of Spark Ignition Engines Applying the Combined Method of Power Regulation

One of the disadvantages of spark ignition engines, whose power is regulated by throttling, is the increased fuel consumption at low loads and when the engine is idle. The combined method of engine power regulation by switching off the cylinder group and throttling working cylinders is one of the effective ways to improve fuel economy in the above-mentioned modes. This article presents the research results of the combined method of engine power regulation which can be realized by minor structural changes in operating conditions. The method implies the following: at low loads and at idle speed of the engine. Fuel supply to the group of cylinders is switched off with the simultaneous increase of the cyclic fuel supply in the working cylinders. The adequacy of the calculated results has been checked by the indication of operating processes in switched off and working cylinders. The research results of a six-cylinder spark ignition engine with the distributed gasoline injection using the combined power regulation system have been shown. The angles of opening the throttle which provides a non-shock transition from the operation with all cylinders to the operation with the cylinder group switched off have been determined.

An Electronic Control Unit for Joint Supply of Fuel and Hydrogen Additives to Diesel Engines of Vehicles

The results of experimental studies of the operation of a D-242 diesel engine with hydrogen additives, as well as on the operation of an aluminum–hydrogen generator, are presented. The main parameters measured in the course of the experiments with the diesel engine and the aluminum–hydrogen generator under their joint operation in an automatic mode are presented. A structural diagram of an electronic control system for joint supply of fuel and hydrogen additives to a diesel engine of a vehicle is presented that makes it possible to maintain a preset crankshaft rotation speed and engine power in an automatic mode. The proposed solutions can improve the efficiency of vehicle diesel engines and, as a result, reduce the fuel consumption and level of hazardous emissions into the environment.